Extrapyramidal symptoms with atypical antipsychotics : incidence, prevention and management.

The treatment of schizophrenia changed drastically with the discovery of antipsychotic medications in the 1950s, the release of clozapine in the US in 1989 and the subsequent development of the atypical or novel antipsychotics. These newer medications differ from their conventional counterparts, primarily based on their reduced risk of extrapyramidal symptoms (EPS). EPS can be categorised as acute (dystonia, akathisia and parkinsonism) and tardive (tardive dyskinesia and tardive dystonia) syndromes. They are thought to have a significant impact on subjective tolerability and adherence with antipsychotic therapy in addition to impacting function. Unlike conventional antipsychotic medications, atypical antipsychotics have a significantly diminished risk of inducing acute EPS at recommended dose ranges. These drugs may also have a reduced risk of causing tardive dyskinesia and in some cases may have the ability to suppress pre-existing tardive dyskinesia. This paper reviews the available evidence regarding the incidence of acute EPS and tardive syndromes with atypical antipsychotic therapy. Estimates of incidence are subject to several confounds, including differing methods for detection and diagnosis of EPS, pretreatment effects and issues surrounding the administration of antipsychotic medications. The treatment of acute EPS and tardive dyskinesia now includes atypical antipsychotic therapy itself, although other adjunctive strategies such as antioxidants have also shown promise in preliminary trials. The use of atypical antipsychotics as first line therapy for the treatment of schizophrenia is based largely on their reduced risk of EPS compared with conventional antipsychotics. Nevertheless, EPS with these drugs can occur, particularly when prescribed at high doses. The EPS advantages offered by the atypical antipsychotics must be balanced against other important adverse effects, such as weight gain and diabetes mellitus, now known to be associated with these drugs.     

Atypical antipsychotics for neuropsychiatric symptoms of dementia: malignant or maligned?

Recent concerns regarding the use of atypical antipsychotics when used for the treatment of neuropsychiatric symptoms in dementia have led to a flurry of studies attempting to re-evaluate their place in therapy. We critically review current evidence on the safety profiles of these agents in patients with behavioural and psychological symptoms of dementia (BPSD) and provide recommendations to guide the clinician. Potential risks with this class of medications include extrapyramidal symptoms (EPS), weight gain, diabetes mellitus, cardiac conduction abnormalities (e.g. corrected QT [QTc] interval prolongation), cerebrovascular adverse events and mortality. Compared with placebo, treatment of BPSD with atypical antipsychotics leads to little or no increase in EPS and no significant weight change. Compared with typical antipsychotics, treatment of BPSD with atypical antipsychotics leads to a reduced risk of EPS, lower incidences of tardive dyskinesias and no significant weight gain. Atypical antipsychotics have not been associated with glucose intolerance, diabetes or hyperlipidaemia in elderly dementia patients. Both typical and atypical antipsychotics have been associated with cardiac conduction abnormalities, with the magnitude of QTc prolongation being slightly smaller with atypical antipsychotics. Randomised controlled trials suggest that atypical antipsychotics are associated with an increased risk of cerebrovascular adverse events, such as stroke, and an increased mortality compared with placebo. However, it appears that typical antipsychotics have similar risks of cerebrovascular adverse events and death. An increased risk of anticholinergic adverse effects and falls must also be considered with both typical and atypical antipsychotics. In summary, atypical antipsychotics are associated with potentially serious adverse events. Before prescribing these medications in elderly dementia patients, baseline EPS, ECG abnormalities and concomitant medications should be assessed, and the presence of cardiovascular, cerebrovascular and metabolic risk factors should be taken into consideration when benefits and risks are being weighed.     

Long-acting injectable antipsychotics in the elderly: guidelines for effective use

The elderly are at increased risk for psychosis because of age-related deterioration of cortical areas and neurochemical changes, comorbid physical illnesses, social isolation, sensory deficits and polypharmacy. The prevalence of psychiatric and neuropsychiatric disorders requiring treatment with an antipsychotic agent is expected to increase dramatically among people aged >64 years. Antipsychotic agents are effective in the treatment of schizophrenia, schizoaffective disorder, behavioural symptoms in patients with dementia, and mood disorders with psychosis. However, failure to adhere to a prescribed medication regimen by patients with psychosis is one of the most frustrating problems faced by mental healthcare providers, because of the high risk of relapse associated with partial compliance. For patients with psychosis who will not or cannot take oral medications on a regular daily basis or have other characteristics, such as memory, vision or auditory impairment, which contribute to partial compliance, long-acting injectable antipsychotic medication offers a solution.Older patients are especially at risk of adverse effects associated with traditional antipsychotic agents, such as motor effects, postural hypotension, excessive sedation, and anticholinergic effects because of age-related pharmacokinetic and pharmacodynamic factors, coexisting medical illnesses and concomitant medications. Therefore, drug dosage recommendations in the elderly are much more conservative than in younger patients. The appropriate starting dose of an antipsychotic in older individuals is 25% of the usual adult dose; total daily maintenance doses ranges from 25-50% of the adult dose.There are few studies regarding the use of depot antipsychotics in elderly patients. Studies that are available indicate that traditional antipsychotic agents given as depot injections are associated with positive outcomes in the elderly. Because the risks for extrapyramidal symptoms and tardive dyskinesia are reduced dramatically with atypical antipsychotics compared with traditional agents, the development of long-acting atypical antipsychotic formulations has been pursued. Of the atypical antipsychotics, risperidone is the first agent to be approved in a long-acting injectable formulation. Unpublished clinical data have revealed that patients treated with long-acting injectable risperidone (25mg, 50mg or 75mg) are more likely to show significant clinical improvement than placebo. In addition, hospitalisation rates decreased continuously and significantly during 1 year of treatment for patients who received long-acting injectable risperidone.Long-acting injectable antipsychotic medication should be considered for older patients for whom long-term treatment is indicated. The choice of which drug to use should be based on patients' history of response and personal preference, clinician's previous experience and pharmacokinetic properties.     

Efficacy of nefazodone in the treatment of neuroleptic induced extrapyramidal side effects: a double-blind randomised parallel group placebo-controlled trial

Many atypical antipsychotics show antagonism at both serotonergic and dopaminergic neurones and show fewer extrapyramidal side effects (EPS). Nefazodone blocks postsynaptic 5HT2A receptors and weakly inhibits serotonin reuptake. This study aimed to elucidate the role of nefazodone in the treatment of antipsychotic-induced EPS. The trial was a double-blind, randomised, placebo-controlled trial of patients requiring antipsychotic treatment with haloperidol 10mg daily; from which a subgroup of patients who developed EPS were selected for the study. Patients were randomised to add-on therapy with either placebo (n=24) or nefazodone (n=25) 100mg bd. EPS were measured on days 0, 3 and 7 using the Simpson Angus, Barnes akathisia, abnormal involuntary movement and Chouinard scales. Nefazodone significantly reduced EPS as measured by both the Simpson Angus scale and CGI (p=0.007 and 0.0247, respectively). Akathisia and tardive dyskinesia did not differ between the two groups (p=0.601; p=0.507, respectively). These results suggest the role of 5HT2 antagonism in the mechanism of action of atypical antipsychotics with respect to lowering rates of drug-induced EPS. In addition, a therapeutic role for nefazodone is suggested in the treatment of antipsychotic-induced EPS.     

A risk-benefit assessment of risperidone for the treatment of behavioural and psychological symptoms in dementia.

The importance of behavioural and psychological symptoms in dementia (BPSD) is increasingly being recognised. Symptoms such as verbal and physical aggression, agitation, sleep disturbances and wandering are common, cause great distress to caregivers and are likely to lead to institutionalisation of patients. At present, these symptoms are also more amenable to treatment compared with the progressive intellectual decline caused by dementing illnesses. The care of individuals with BPSD involves a broad range of psychosocial treatments for the patient and his or her family. If pharmacotherapy is deemed necessary to manage BPSD, a careful balance must be struck between the benefits of symptom control and the inherent risks associated with most psychotropic agents in the elderly. Elderly patients in general, and patients with dementia in particular, are more sensitive to medication adverse effects, including anticholinergic effects, orthostatic hypotension, sedation, parkinsonism, tardive dyskinesia and cognitive impairment than younger patients with dementia or individuals without dementia. To date, treatment of symptoms of aggression and psychosis has relied on the empirical use of antidepressants, anxiolytics, typical antipsychotics (neuroleptics) and other agents. Treatment-limiting adverse effects are frequently reported with all of these agents. However, it is the typical antipsychotics and the atypical antipsychotic clozapine that are associated with the greatest risk of adverse effects in the elderly. The present review highlights the issues that limit the use of older psychotropic agents in the elderly, and presents an assessment of the available evidence concerning the efficacy, safety and tolerability of the atypical antipsychotic risperidone, in the treatment of BPSD in elderly patients with dementia. The extensive clinical development programme for risperidone has shown the drug to be effective and well tolerated in many fragile patients. As a result of its efficacy and safety profile, risperidone can be used for the treatment of behavioural and psychological symptoms in patients with dementia. Risperidone therefore represents a significant addition to the armamentarium for BPSD. While efforts continue in the development of treatment for the cognitive decline associated with dementia, treatment is now available for the noncognitive symptoms. By treating the latter, risperidone has the potential to be of substantial benefit to patients with dementia, their carers and the costs of healthcare.     

Quetiapine. A review of its use in the management of schizophrenia

Quetiapine (Seroquel), a dibenzothiazepine derivative, is an atypical antipsychotic with demonstrated efficacy in acute schizophrenia. In short-term, randomised, double-blind trials, it was usually more effective than placebo, and was generally effective against both positive and negative symptoms. Overall, quetiapine (up to 750 mg/day) was at least as effective as chlorpromazine (up to 750 mg/day) and had similar efficacy to haloperidol (up to 16 mg/day) in patients with acute schizophrenia in randomised, double-blind trials; it was at least as effective as haloperidol 20 mg/day in patients with schizophrenia unresponsive or partially responsive to previous antipsychotic treatment. Improvements in overall psychopathology and positive and negative symptoms with quetiapine (up to 800 mg/day) were similar to those with risperidone (up to 8 mg/day) or olanzapine (15 mg/day) [interim analysis]. Efficacy was maintained for at least 52 weeks in open-label follow-up studies in adult and elderly patients. Quetiapine improved cognitive function versus haloperidol, and depressive symptoms and hostility/aggression versus placebo. Quetiapine is well tolerated. It is associated with placebo-level incidence of extrapyramidal symptoms (EPS) across its entire dose range, appears to have a low risk for EPS in vulnerable patient groups (e.g. the elderly, adolescents or patients with organic brain disorders) and has a more favourable EPS profile than risperidone. Irrespective of dose, quetiapine, unlike risperidone and amisulpride, does not elevate plasma prolactin levels compared with placebo, and previously elevated levels may even normalise. Quetiapine appears to have minimal short-term effects on bodyweight and a favourable long-term bodyweight profile. Preliminary studies indicate that there is a high level of patient acceptability and satisfaction with quetiapine. In conclusion, quetiapine has shown efficacy against both positive and negative symptoms of schizophrenia, and has benefits in improving cognitive deficits, affective symptoms and aggression/hostility. The beneficial effects of quetiapine have been maintained for at least 52 weeks. Quetiapine was effective and well tolerated in hard-to-treat patients, and may be of particular use in these individuals. It is at least as effective as standard antipsychotics and appears to have similar efficacy to risperidone and olanzapine. The relative risk/benefit profile of quetiapine compared with other atypical antipsychotics requires further research in head-to-head trials, although quetiapine's relatively benign tolerability profile distinguishes it from other commonly used atypical agents, particularly with respect to bodyweight, EPS and plasma prolactin levels. Overall, quetiapine has an excellent risk/benefit profile and is a suitable first-line option for the treatment of schizophrenia.     

Review of quetiapine and its clinical applications in schizophrenia

Preclinical studies have shown that quetiapine (Seroquel, AstraZeneca) is an atypical antipsychotic with many similarities to clozapine. Both placebo-controlled and comparative studies in patients with schizophrenia have demonstrated that quetiapine has long-term efficacy in both positive and negative domains, as well as beneficial effects on affective and cognitive symptoms. Comparative clinical studies confirm that quetiapine is at least as effective as the standard antipsychotics, chlorpromazine and haloperidol and response rates with quetiapine are similar to those reported with other atypical antipychotics. Quetiapine has also demonstrated superior efficacy to haloperidol in partially responsive patients, who can be particularly difficult to treat. Quetiapine has a wide clinical dosing range (150-750 mg/day), although doses of 400 mg or above should be used in patients who do not fully respond to lower doses of the drug. Quetiapine is generally well tolerated with no requirement for routine ECG or blood monitoring and it has minimal effects on weight. Uniquely among other first-line atypical antipsychotics, quetiapine is associated with a placebo-level incidence of EPS and an indistinguishable effect from placebo on plasma prolactin at all doses. Thus, clinicians can confidently increase the dose of quetiapine, without increasing the risk of EPS or hyperprolactinaemia. A number of studies have also shown that quetiapine is well-tolerated and effective in patients who are particularly susceptible to EPS, including elderly and adolescent patients and those with pre-existing dopaminergic pathology, such as Alzheimer's disease and Parkinson's disease. The consistent efficacy in treating all schizophrenic domains and good tolerability, particularly placebo-level EPS, make quetiapine acceptable to patients, as demonstrated in a survey of patient satisfaction. Thus quetiapine is a suitable first-line therapy for the treatment of schizophrenia and psychosis.     

Intramuscular preparations of antipsychotics: uses and relevance in clinical practice

Intramuscular formulations of antipsychotics can be sub-divided into two groups on the basis of their pharmacokinetic features: short-acting preparations and long-acting or depot preparations. Short-acting intramuscular formulations are used to manage acute psychotic episodes. On the other hand, long-acting compounds, also called "depot", are administered as antipsychotic maintenance treatment to ensure compliance and to eliminate bioavailability problems related to absorption and first pass metabolism. Adverse effects of antipsychotics have been studied with particular respect to oral versus short- and long-acting intramuscular formulations of the different compounds. For short-term intramuscular preparations the main risk with classical compounds are hypotension and extrapyramidal side effects (EPS). Data on the incidence of EPS with depot formulations are controversial: some studies point out that the incidence of EPS is significantly higher in patients receiving depot preparations, whereas others show no difference between oral and depot antipsychotics. Studies on the strategies for switching patients from oral to depot treatment suggest that this procedure is reasonably well tolerated, so that in clinical practice depot antipsychotic therapy is usually begun while the oral treatment is still being administered, with gradual tapering of the oral dose. Efficacy, pharmacodynamics and clinical pharmacokinetics of haloperidol decanoate, fluphenazine enanthate and decanoate, clopenthixol decanoate, zuclopenthixol decanoate and acutard, flupenthixol decanoate, perphenazine enanthate, pipothiazine palmitate and undecylenate, and fluspirilene are reviewed. In addition, the intramuscular preparations of atypical antipsychotics and clinical uses are reviewed. Olanzapine and ziprasidone are available only as short-acting preparations, while risperidone is to date the only novel antipsychotic available as depot formulation. To date, acutely ill, agitated psychotic patients have been treated with high parenteral doses of typical antipsychotics, which often cause serious EPS, especially dystonic reactions. Intramuscular formulations of novel antipsychotics (olanzapine and ziprasidone), which appear to have a better tolerability profile than typical compounds, showed an equivalent efficacy to parenteral typical agents in the acute treatment of psychoses. However, parenteral or depot formulations of atypical antipsychotics are not yet widely available.     

Association of diabetes with dyskinesia in older psychosis patients

Rationale Older patients treated with antipsychotics are more likely to develop tardive dyskinesia (TD) than younger individuals. Advanced age is also an important risk factor for diabetes, which may be associated with TD. These observations suggest that older diabetic patients may be particularly vulnerable to developing TD.Objective To examine whether older psychosis patients with diabetes exhibit more severe dyskinesia than well-matched patients without diabetes and to test whether there are differences in dyskinesia severity between diabetic patients treated with conventional versus atypical antipsychotics versus those not taking antipsychotic medications.Method Sixty-one psychosis patients with diabetes and 122 case-matched non-diabetic comparison patients were studied. Observer-based and quantitative instrumental measures were administered to assess prevalence and severity of dyskinesia. Raters were unaware of patients diabetes status.Results Diabetic patients exhibited significantly more severe TD than non-diabetic comparison patients. Groups did not differ in terms of severity of parkinsonism. Significantly more diabetic (27.9%) than non-diabetic (14.6%) patients met research diagnostic criteria for TD. Diabetic patients treated with atypical antipsychotics at the time of assessment had significantly more severe TD than all other patient subgroups, including patients treated with conventional antipsychotics. Results from the instrumental measures of force steadiness were consistent with observer-based severity ratings.Conclusion The deleterious effect of diabetes on TD in the absence of any effect of parkinsonism supports preclinical studies of glucose-related dopamine hyperfunction and has implications for the pharmacologic management of psychosis in patients with pre-existing diabetes.     

Comparison of risk of cerebrovascular events in an elderly VA population with dementia between antipsychotic and nonantipsychotic users

INTRODUCTION: The credibility of an increased risk of cerebrovascular events (CVEs) in elderly patients with dementia being treated with second-generation antipsychotics (SGAs) is debatable. Although early published and unpublished data indicated a risk, much of the subsequent literature has not supported this initial finding. Previously published studies were flawed in part because they lacked a control group and did not stratify by dementia subtype. This study examined the risk of a CVE in patients diagnosed with Alzheimer or vascular dementia while being treated with SGA, first-generation antipsychotics, or no antipsychotic medication. METHODS: Data from 14,029 patients aged 65 years and older were evaluated using patient information from Veterans Administration and Medicare databases. Patients who received care for dementia were categorized according to dementia subtype (vascular or Alzheimer) and antipsychotic use during an 18-month period. Patients were observed until they were admitted to a hospital for a CVE, stopped taking or switched antipsychotics, died, or until the 18-month observation period ended. RESULTS: Overall, CVE risk did not differ whether patients were receiving a first-generation antipsychotic, SGA, or no antipsychotic therapy. However, patients with vascular dementia had an increased risk in hospitalization for a CVE. There was no increase in risk of a CVE for patients treated with quetiapine, olanzapine, or risperidone relative to haloperidol, or for patients receiving olanzapine or risperidone relative to quetiapine. Stratified subgroup analyses demonstrated no difference in risk for CVE-related admission patients with Alzheimer dementia among individual agents. However, patients with vascular dementia receiving risperidone, but not olanzapine or quetiapine, were found to be at decreased risk for CVE admission relative to haloperidol. CONCLUSIONS: This study found no increase in overall risk for CVE-related hospital admission in patients treated with antipsychotic medications.     

The use of atypical antipsychotics in the management of schizophrenia

Long-term drug treatment of schizophrenia with conventional antipsychotics has limitations: an estimated quarter to one third of patients are treatment-resistant; conventional antipsychotics have only a modest impact upon negative symptoms (poverty of thought, social withdrawal and loss of affect); and adverse effects, particularly extrapyramidal symptoms (EPS). Newer, so-called atypical, antipsychotics such as olanzapine, risperidone, sertindole and clozapine (an old drug which was re-introduced in 1990) are claimed to address these limitations. Atypical agents are, at a minimum, at least as effective as conventional drugs such as haloperidol. They also cause substantially fewer extrapyramidal symptoms. However, some other adverse effects are more common than with conventional drugs. For example, clozapine carries a significant risk of serious blood disorders, for which special monitoring is mandatory; it also causes troublesome drowsiness and increased salivation more often than conventional agents. Some atypical agents cause more weight gain or QT prolongation than older agents. The choice of therapy is, therefore, not straightforward. At present, atypical agents represent an advance for patients with severe or intolerable EPS. Most published evidence exists to support the use of clozapine, which has also been shown to be effective in schizophrenia refractory to conventional agents. However, the need for compliance with blood count monitoring and its sedative properties make careful patient selection important. The extent of any additional direct benefit offered by atypical agents on negative symptoms is not yet clear. The lack of a depot formulation for atypical drugs may pose a significant practical problem. To date, only two double-blind studies in which atypical agents were compared directly have been published. Neither provides compelling evidence for the choice of one agent over another. Atypical agents are many times more expensive than conventional drugs. Although drug treatment constitutes only a small proportion of the costs of managing schizophrenia, the additional annual cost of the use of atypical agents in, say, a quarter of the likely U.K. schizophrenic population would be about 56 M pound sterling. There is only limited evidence of cost-effectiveness. Atypical antipsychotics are not currently licensed for other conditions where conventional antipsychotics are commonly used, such as behaviour disturbance or dementia in the elderly. Their dose, and place in treatment in such cases have yet to be determined.     

Review of quetiapine and its clinical applications in schizophrenia

Preclinical studies have shown that quetiapine (Seroquel?, AstraZeneca) is an atypical antipsychotic with many similarities to clozapine. Both placebo-controlled and comparative studies in patients with schizophrenia have demonstrated that quetiapine has long-term efficacy in both positive and negative domains, as well as beneficial effects on affective and cognitive symptoms. Comparative clinical studies confirm that quetiapine is at least as effective as the standard antipsychotics, chlorpromazine and haloperidol and response rates with quetiapine are similar to those reported with other atypical antipychotics. Quetiapine has also demonstrated superior efficacy to haloperidol in partially responsive patients, who can be particularly difficult to treat. Quetiapine has a wide clinical dosing range (150 - 750 mg/day), although doses of 400 mg or above should be used in patients who do not fully respond to lower doses of the drug. Quetiapine is generally well tolerated with no requirement for routine ECG or blood monitoring and it has minimal effects on weight. Uniquely among other first-line atypical antipsychotics, quetiapine is associated with a placebo-level incidence of extrapyramidal side-effects (EPS) and an indistinguishable effect from placebo on plasma prolactin at all doses. Thus, clinicians can confidently increase the dose of quetiapine, without increasing the risk of EPS or hyperprolactinaemia. A number of studies have also shown that quetiapine is well-tolerated and effective in patients who are particularly susceptible to EPS, including elderly and adolescent patients and those with pre-existing dopaminergic pathology, such as Alzheimer’s disease and Parkinson’s disease. The consistent efficacy in treating all schizophrenic domains and good tolerability, particularly placebo-level EPS, make quetiapine acceptable to patients, as demonstrated in a survey of patient satisfaction. Thus quetiapine is a suitable first-line therapy for the treatment of schizophrenia and psychosis.     

Antipsychotic-induced venous thromboembolism: a review of the evidence

Psychiatric disorders themselves and treatment with conventional antipsychotic medications have in a number of early studies been associated with venous thromboembolism. In general, information on the relationship between antipsychotics and this possible adverse effect is in the form of case reports and open cross-sectional studies. However, recently the association between conventional antipsychotics and venous thrombosis has been strengthened as a result of the publication of a large, nested, case-control study. In this study, low-potency antipsychotic drugs were more strongly associated with venous thrombosis than high-potency drugs. In addition, recent epidemiological data support an association between the atypical antipsychotic agent clozapine and venous thromboembolism. The risk for venous thromboembolism seems to be highest during the initial months of treatment with antipsychotics. The biological mechanisms responsible for this possible adverse drug reaction are unknown, but a number of hypotheses have been suggested. The increased risk may be the result of drug-induced sedation, obesity, hyperleptinaemia, antiphospholipid antibodies and increased activity in the coagulation system. The association could also be related to underlying risk factors present in patients with psychosis such as smoking. Despite the limitations of present knowledge, clinicians should be aware of this possible adverse drug reaction and should consider interrupting or changing the antipsychotic regimen in patients in whom this reaction is suspected. More studies are needed in order to further elucidate this adverse effect, particularly to determine the incidence rate, possible predisposing factors and the biological mechanisms involved.     

Choosing an atypical antipsychotic

The atypical antipsychotics vary in terms of their pharmacological profiles, particularly in relation to their tolerability, effects on safety parameters and patient acceptability. Olanzapine, risperidone and ziprasidone are associated with extrapyramidal symptoms (EPS) in a dose-dependent manner, whereas quetiapine has been shown to produce a significantly lower incidence of substantial EPS effects than haloperidol, and less EPS requiring treatment than risperidone. Similarly, unlike risperidone and haloperidol, quetiapine treatment has been associated with a significant reduction in serum prolactin levels, and has normalized raised prolactin levels after discontinuation of previous treatment. Weight gain is also one of the major unwanted adverse effects of treatment with many antipsychotic drugs but, in contrast, quetiapine has demonstrated a neutral or 'normalizing' effect on body weight. In comparison with other antipsychotics, quetiapine has been shown to possess a favourable safety profile, with no requirement for routine blood, thyroid, or liver monitoring during treatment. Overall, quetiapine therapy has produced high levels of patient satisfaction and compliance and this, coupled with its efficacy in reducing psychoses of various origins, has made it an attractive treatment option in both patients at increased risk of EPS, and the general population.     

Antipsychotics produce locomotor impairment in larval zebrafish

Zebrafish has been a favored vertebrate genetic model organism for studying developmental processes. It also holds a great potential for understanding the genetic basis of behavior and associated behavioral disorders. Despite such potential, their use in the study of behavior is greatly under-explored. It is well known that multiple classes of drugs used to treat psychiatric diseases produce extrapyramidal side (EPS) effects and consequent movement disorders in humans. The underlying molecular causes of these drug-induced movement disorders are poorly understood. Here we report that zebrafish treated with the antipsychotics fluphenazine and haloperidol (both of which can induce severe EPS in humans) develop movement defects. In contrast, another antipsychotic olanzapine, which produces mild to little EPS in humans, leads to minimal movement defects in zebrafish. These results establish a rapid assay system in which the effects of EPS-inducing agents can be assessed. Thus, future genetic screening in zebrafish shall identify genes and pathways that elucidate drug-induced movement disorder in human as well as provide insights into the brain control of locomotor activity. Future chemical screening in zebrafish may act as a preclinical test for the EPS effect of certain drugs, as well as a test used to researching drugs made to counteract the effects of EPS.     

Relapse of tardive dyskinesia due to reduction in clozapine dose

Clozapine is a second-generation (atypical) antipsychotic agent, which has been proven efficient against the positive and negative symptoms of schizophrenia, with a low propensity to induce tardive dyskinesia (TD). Compared with typical antipsychotics, it has a greater affinity for dopamine D4 than D2 receptors and additional action on serotonin 5-HT_2A receptors. Due to its weak D₂ blocking action, it produces few extra pyramidal side effects and TD is rare. TD is one of the muscular side effects of antipsychotic drugs, especially the older generation like haloperidol. TD does not occur until after many months or years of taking antipsychotic drugs. TD is primarily characterized by abnormal involuntary movements of the tongue, lips or jaw, as well as facial grimacing or extremities that develop in association with the use of antipsychotic medications. TD can be embarrassing to the affected patient in public. The movements disappear during sleep and women are at greater risk than men for developing TD.     

Antipsychotic-induced extrapyramidal side effects in bipolar disorder and schizophrenia: a systematic review

OBJECTIVES: Newer atypical antipsychotics have been reported to cause a lower incidence of extrapyramidal side effects (EPS) than conventional agents. This review is to compare antipsychotic-induced EPS relative to placebo in bipolar disorder (BPD) and schizophrenia. METHODS: English-language literature cited in Medline was searched with terms antipsychotics, placebo-controlled trial, and bipolar disorder or schizophrenia and then with antipsychotic (generic/brand name), safety, akathisia, EPS, or anticholinergic use, bipolar mania/depression, BPD, or schizophrenia, and randomized clinical trial. Randomized, double-blind, placebo-controlled, monotherapy studies with comparable doses in both BPD and schizophrenia were included. Absolute risk increase and number needed to treat to harm (NNTH) for akathisia, overall EPS, and anticholinergic use relative to placebo were estimated. RESULTS: Eleven trials in mania, 4 in bipolar depression, and 8 in schizophrenia were included. Haloperidol significantly increased the risk for akathisia, overall EPS, and anticholinergic use in both mania and schizophrenia, with a larger magnitude in mania, an NNTH for akathisia of 4 versus 7, EPS of 3 versus 5, and anticholinergic use of 2 versus 4, respectively Among atypical antipsychotics, only ziprasidone significantly increased the risk for overall EPS and anticholinergic use in both mania and schizophrenia, again with larger differences in mania, an NNTH for overall EPS of 11 versus 19, and anticholinergic use of 5 versus 9. In addition, risks were significantly increased for overall EPS (NNTH = 5) and anticholinergic use (NNTH = 5) in risperidone-treated mania, akathisia in aripiprazole-treated mania (NNTH = 9) and bipolar depression (NNTH = 5), and overall EPS (NNTH = 19) in quetiapine-treated bipolar depression. CONCLUSIONS: Bipolar patients, especially in depression, were more vulnerable to having acute antipsychotic-induced movement disorders than those with schizophrenia.     

All-cause mortality associated with atypical and typical antipsychotics in demented outpatients

PURPOSE: To estimate the association between use of typical and atypical antipsychotics and all-cause mortality in a population of demented outpatients. METHODS: The study cohort comprised all demented patients older than 65 years and registered in the Integrated Primary Care Information (IPCI) database, during 1996-2004. First, mortality rates were calculated during use of atypical and typical antipsychotics. Second, we assessed the association between use of atypical and typical antipsychotics and all-cause mortality through a nested case-control study in the cohort of demented patients. Each case was matched to all eligible controls at the date of death by age and duration of dementia. Odds ratios were estimated through conditional logistic regression analyses. RESULTS: The crude mortality rate was 30.1 (95%CI: 18.2-47.1) and 25.2 (21.0-29.8) per 100 person-years (PY) during use of atypical and typical antipsychotics, respectively. No significant difference in risk of death was observed between current users of atypical and typical antipsychotics (OR = 1.3; 95%CI: 0.7-2.4). Both types of antipsychotics were associated with a significantly increased risk of death as compared to non-users (OR = 2.2, 1.2-3.9 for atypical antipsychotics; OR=1.7, 1.3-2.2 for typical antipsychotics). CONCLUSIONS: Conventional antipsychotic drug should be included in the FDA's Public Health advisory, which currently warns only of the increased risk of death with the use of atypical antipsychotics in elderly demented persons.     

Treating psychosis in movement disorder patients: a review

Introduction: Psychosis is a major psychiatric problem that often occurs at the interface of psychiatry and the neurological specialty of movement disorders. Psychotic syndromes are common in treated movement disorder patients, and almost all antipsychotic drugs produce movement disorders. There is little published data on psychosis in movement disorders aside from Parkinson’s disease (PD).

Areas covered: In this review, we focus primarily on PD, in which about 30% of treated patients have visual hallucinations and 5 – 10% have paranoid delusions; dementia with Lewy bodies, a variant of PD in which dementia occurs early and psychotic symptoms are common; Huntington’s disease (HD), an inherited disorder that causes behavioral problems, frequently including psychosis; and tardive dyskinesia (TD), a group of movement disorder syndromes caused by antipsychotic drugs. All articles were reviewed in each of the more common movement disorders and indexed in PubMed with keywords including psychosis, psychotic symptoms, antipsychotics, hallucinations and delusions.

Expert opinion: Although there are no approved drugs for treating psychotic symptoms in any of the movement disorders, pimavanserin, a 5-HT_2A inverse agonist, is thought likely to gain approval in 2015 for treating PD psychosis. We present evidence that clozapine is currently the drug of choice for treating psychosis in patients with parkinsonism; however, blood monitoring requirements make it difficult to use. The choice of treatment of hyperkinetic disorders such as HD and the TD disorders depends on the clinical scenario.